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1.
Cell Death Discov ; 10(1): 303, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926351

RESUMO

Head and neck squamous cell carcinomas (HNSCCs) are amongst the most aggressive, complex, and heterogeneous malignancies. The standard of care treatments for HNC patients include surgery, radiotherapy, chemotherapy, or their combination. However, around 50% do not benefit while suffering severe toxic side effects, costing the individuals and society. Decades have been spent to improve HNSCC treatment outcomes with only limited success. Much of the research in HNSCC treatment has focused on understanding the genetics of the HNSCC malignant cells, but it has become clear that tumour microenvironment (TME) plays an important role in the progression as well as treatment response in HNSCC. Understanding the crosstalk between cancer cells and TME is crucial for inhibiting progression and treatment resistance. Cancer-associated fibroblasts (CAFs), the predominant component of stroma in HNSCC, serve as the primary source of extra-cellular matrix (ECM) and various pro-tumoral composites in TME. The activation of CAFs in HNSCC is primarily driven by cancer cell-secreted molecules, which in turn induce phenotypic changes, elevated secretive status, and altered ECM production profile. Concurrently, CAFs play a pivotal role in modulating the cell cycle, stemness, epithelial-mesenchymal transition (EMT), and resistance to targeted and chemoradiotherapy in HNSCC cells. This modulation occurs through interactions with secreted molecules or direct contact with the ECM or CAF. Co-culture and 3D models of tumour cells and other TME cell types allows to mimic the HNSCC tumour milieu and enable modulating tumour hypoxia and reprograming cancer stem cells (CSC). This review aims to provide an update on the development of HNSCC tumour models comprising CAFs to obtain better understanding of the interaction between CAFs and tumour cells, and for providing preclinical testing platforms of current and combination with emerging therapeutics.

2.
Oncol Rep ; 51(6)2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38606512

RESUMO

As a member of BET (bromodomain and extra-terminal) protein family, BRD4 (bromodomain­containing protein 4) is a chromatin­associated protein that interacts with acetylated histones and actively recruits regulatory proteins, leading to the modulation of gene expression and chromatin remodeling. The cellular and epigenetic functions of BRD4 implicate normal development, fibrosis and inflammation. BRD4 has been suggested as a potential therapeutic target as it is often overexpressed and plays a critical role in regulating gene expression programs that drive tumor cell proliferation, survival, migration and drug resistance. To address the roles of BRD4 in cancer, several drugs that specifically target BRD4 have been developed. Inhibition of BRD4 has shown promising results in preclinical models, with several BRD4 inhibitors undergoing clinical trials for the treatment of various cancers. Head and neck squamous cell carcinoma (HNSCC), a heterogeneous group of cancers, remains a health challenge with a high incidence rate and poor prognosis. Conventional therapies for HNSCC often cause adverse effects to the patients. Targeting BRD4, therefore, represents a promising strategy to sensitize HNSCC to chemo­ and radiotherapy allowing de­intensification of the current therapeutic regime and subsequent reduced side effects. However, further studies are required to fully understand the underlying mechanisms of action of BRD4 in HNSCC in order to determine the optimal dosing and administration of BRD4­targeted drugs for the treatment of patients with HNSCC.


Assuntos
Neoplasias de Cabeça e Pescoço , Proteínas Nucleares , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fatores de Transcrição/genética , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Histonas/metabolismo , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/genética , Linhagem Celular Tumoral , Proteínas que Contêm Bromodomínio
3.
Cell Death Dis ; 14(12): 831, 2023 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-38097548

RESUMO

Malignant melanoma (MM) is known to be intrinsically chemoresistant, even though only ~20% of MM carry mutations of the tumor suppressor p53. Despite improvement of systemic therapy the mortality rate of patients suffering from metastatic MM is still ~70%, highlighting the need for alternative treatment options or for the re-establishment of conventional therapeutic approaches, including chemotherapy. Screening the p53 mutation status in a cohort of 19 patient-derived melanoma samples, we identified one rarely described missense mutation of p53 leading to E285K amino acid exchange (mutp53(E285K)). Employing structural and computational analysis we revealed a major role of E285 residue in maintaining stable conformation of wild-type p53 (wtp53). E285K mutation was predicted to cause interruption of a salt-bridge network affecting the conformation of the C-terminal helix of the DNA-binding domain (DBD) thereby preventing DNA interaction. In this context, a cluster of frequently mutated amino acid residues in cancer was identified to putatively lead to similar structural effects as E285K substitution (E285 cluster). Functional analysis, including knockdown of endogenous p53 and reconstitution with diverse p53 missense mutants confirmed mutp53(E285K) to have lost transcriptional activity, to be localized in the cytosol of cancer cells, by both means conferring chemoresistance. Re-sensitization to cisplatin-induced cell death was achieved using clinically approved compounds aiming to restore p53 wild-type function (PRIMA1-Met), or inhibition of AKT-driven MAPK survival pathways (afuresertib), in both cases being partially due to ferroptosis induction. Consequently, active ferroptosis induction using the GPX4 inhibitor RSL3 proved superior in tumorselectively fighting MM cells. Due to high prevalence of the E285-cluster mutations in MM as well as in a variety of other tumor types, we conclude this cluster to serve an important function in tumor development and therapy and suggest new implications for ferroptosis induction in therapeutic applications fighting MM in particular and cancer in general.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Melanoma , Neoplasias Cutâneas , Proteína Supressora de Tumor p53 , Humanos , Aminoácidos , Linhagem Celular Tumoral , Citosol/metabolismo , DNA , Resistencia a Medicamentos Antineoplásicos/genética , Melanoma/tratamento farmacológico , Melanoma/genética , Mutação , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/genética , Proteína Supressora de Tumor p53/metabolismo
4.
Chem Sci ; 14(14): 3881-3892, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37035694

RESUMO

Apoptin is a small viral protein capable of inducing cell death selectively in cancer cells. Despite its potential as an anticancer agent, relatively little is known about its mechanism of toxicity and cancer-selectivity. Previous experiments suggest that cancer-selective phosphorylation modulates apoptin toxicity, although a lack of chemical tools has hampered the dissection of underlying mechanisms. Here, we describe structure-function studies with site-specifically phosphorylated apoptin (apoptin-T108ph) in living cells which revealed that Thr108 phosphorylation is the selectivity switch for apoptin toxicity. Mechanistic investigations link T108ph to actin binding, cytoskeletal disruption and downstream inhibition of anoikis-resistance as well as cancer cell invasion. These results establish apoptin as a protein pro-drug, selectively activated in cancer cells by phosphorylation, which disrupts the cytoskeleton and promotes cell death. We anticipate that this mechanism provides a framework for the design of next generation anticancer proteins with enhanced selectivity and potency.

5.
Cell Death Dis ; 13(11): 921, 2022 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-36333293

RESUMO

EGFR upregulation is an established biomarker of treatment resistance and aggressiveness in head and neck cancers (HNSCC). EGFR-targeted therapies have shown benefits for HPV-negative HNSCC; surprisingly, inhibiting EGFR in HPV-associated HNSCC led to inferior therapeutic outcomes suggesting opposing roles for EGFR in the two HNSCC subtypes. The current study aimed to understand the link between EGFR and HPV-infected HNSCC particularly the regulation of HPV oncoproteins E6 and E7. We demonstrate that EGFR overexpression suppresses cellular proliferation and increases radiosensitivity of HPV-positive HNSCC cell lines. EGFR overexpression inhibited protein expression of BRD4, a known cellular transcriptional regulator of HPV E6/E7 expression and DNA damage repair facilitator. Inhibition of EGFR by cetuximab restored the expression of BRD4 leading to increased HPV E6 and E7 transcription. Concordantly, pharmacological inhibition of BRD4 led to suppression of HPV E6 and E7 transcription, delayed cellular proliferation and sensitised HPV-positive HNSCC cells to ionising radiation. This effect was shown to be mediated through EGFR-induced upregulation of microRNA-9-5p and consequent silencing of its target BRD4 at protein translational level, repressing HPV E6 and E7 transcription and restoring p53 tumour suppressor functions. These results suggest a novel mechanism for EGFR inhibition of HPV E6/E7 oncoprotein expression through an epigenetic pathway, independent of MAPK, but mediated through microRNA-9-5p/BRD4 regulation. Therefore, targeting EGFR may not be the best course of therapy for certain cancer types including HPV-positive HNSCC, while targeting specific signalling pathways such as BRD4 could provide a better and potentially new treatment to improve HNSCC therapeutic outcome.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , MicroRNAs , Proteínas Oncogênicas Virais , Infecções por Papillomavirus , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Proteínas E7 de Papillomavirus/genética , Proteínas E7 de Papillomavirus/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/uso terapêutico , Carcinoma de Células Escamosas/patologia , Proteínas Repressoras/metabolismo , Linhagem Celular Tumoral , Fatores de Transcrição/genética , Fatores de Transcrição/uso terapêutico , Proteínas Oncogênicas Virais/genética , Proteínas Oncogênicas Virais/metabolismo , Neoplasias de Cabeça e Pescoço/genética , MicroRNAs/genética , MicroRNAs/uso terapêutico , Receptores ErbB/genética , Receptores ErbB/metabolismo , Proteínas de Ciclo Celular/genética
6.
Elife ; 102021 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-33929322

RESUMO

High-dimensional cytometry is an innovative tool for immune monitoring in health and disease, and it has provided novel insight into the underlying biology as well as biomarkers for a variety of diseases. However, the analysis of large multiparametric datasets usually requires specialist computational knowledge. Here, we describe ImmunoCluster (https://github.com/kordastilab/ImmunoCluster), an R package for immune profiling cellular heterogeneity in high-dimensional liquid and imaging mass cytometry, and flow cytometry data, designed to facilitate computational analysis by a nonspecialist. The analysis framework implemented within ImmunoCluster is readily scalable to millions of cells and provides a variety of visualization and analytical approaches, as well as a rich array of plotting tools that can be tailored to users' needs. The protocol consists of three core computational stages: (1) data import and quality control; (2) dimensionality reduction and unsupervised clustering; and (3) annotation and differential testing, all contained within an R-based open-source framework.


Assuntos
Alergia e Imunologia , Biologia Computacional/métodos , Citometria de Fluxo/métodos , Algoritmos , Linfócitos B/citologia , Linfócitos B/imunologia , Análise de Dados , Humanos
7.
Transl Oncol ; 14(3): 101017, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33465746

RESUMO

Most solid tumors, such as head and neck cancers, feature a hypoxic microenvironment due to angiogenic dysregulation and the consequent disruption of their vascular network. Such nutrient-deprived environment can induce genomic changes in several tumor cell populations, conferring survival and proliferative advantages to cancer cells through immunosuppression, metabolic switches and enhanced invasiveness. These transcriptional changes, together with the selective pressure hypoxia exerts on cancer cells, leads to the propagation of more aggressive and stress-resistant subpopulations increasing therapy resistance and worsening patient outcomes. Although extensive preclinical and clinical studies involving hypoxia-targeted drugs have been performed, most of these drugs have failed late-stage clinical trials and only a few have managed to be implemented in clinical practice. Here, we provide an overview of three main strategies to target tumor hypoxia: HIF-inhibitors, hypoxia-activated prodrugs and anti-angiogenic agents; summarizing the clinical advances that have been made over the last decade. Given that most hypoxia-targeted drugs seem to fail clinical trials because of insufficient drug delivery, combination with anti-angiogenic agents is proposed for the improvement of therapy response via vascular normalization and enhanced drug delivery. Furthermore, we suggest that using novel nanoparticle delivery strategies might further improve the selectivity and efficiency of hypoxia-targeted therapies and should therefore be taken into consideration for future therapeutic design. Lastly, recent findings point out the relevance that hypoxia-targeted therapy is likely to have in head and neck cancer as a chemo/radiotherapy sensitizer for treatment efficiency improvement.

8.
Cancer Lett ; 498: 80-97, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33137407

RESUMO

High-risk Human Papillomavirus (HPV) infections have recently emerged as an independent risk factor in head and neck squamous cell carcinoma (HNSCC). There has been a marked increase in the incidence of HPV-induced HNSCC subtype, which demonstrates different genetics with better treatment outcome. Despite the favourable prognosis of HPV-HNSCC, the treatment modality, consisting of high dose radiotherapy (RT) in combination with chemotherapy (CT), remains similar to HPV-negative tumours, associated with toxic side effects. Epidermal growth factor receptor (EGFR) is overexpressed in over 80% of HNSCC and correlates with RT resistance. EGFR inhibitor Cetuximab is the only FDA approved targeted therapy for both HNSCC subtypes, however the response varies between HNSCC subtypes. In HPV-negative HNSCC, Cetuximab sensitises HNSCC to RT improving survival rates. To reduce adverse cytotoxicity of CT, Cetuximab has been approved for treatment de-escalation of HPV-positive HNSCC. The results of several recent clinical trials have concluded differing outcome to HPV-negative HNSCC. Here we investigated the role of EGFR in HPV-positive HNSCC response to RT. Remarkably, in HPV-positive HNSCC cell lines and in vivo tumour models, EGFR activation was strongly indicative of increased RT response. In response to RT, EGFR activation induced impairment of DNA damage repair and increased RT response. Furthermore, EGFR was found to downregulate HPV oncoproteinE6 expression and induced p53 activity in response to RT. Collectively, our data uncovers a novel role for EGFR in virally induced HNSCC and highlights the importance of using EGFR-targeted therapies in the context of the genetic makeup of cancer.


Assuntos
Dano ao DNA/genética , Reparo do DNA/imunologia , Neoplasias de Cabeça e Pescoço/genética , Proteínas Oncogênicas Virais/genética , Infecções por Papillomavirus/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/virologia , Animais , Linhagem Celular , Linhagem Celular Tumoral , Cetuximab/farmacologia , Reparo do DNA/efeitos dos fármacos , Reparo do DNA/genética , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Receptores ErbB/genética , Células HEK293 , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Neoplasias de Cabeça e Pescoço/virologia , Humanos , Camundongos , Camundongos Endogâmicos NOD , Infecções por Papillomavirus/virologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/radioterapia
9.
Oral Oncol ; 110: 104972, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33011636

RESUMO

Complex interactions take place during cancer formation and progression. In this regard, there has been increasing focus on the non-malignant cells that make up the tumour microenvironment (TME), and how they interact with malignant tumour cells. TME is highly heterogeneous and has a major influence on tumour behaviour and therapy response. Cancer-associated fibroblasts (CAFs), one of the main components of the TME, establish dangerous liaisons with cancer cells and other components of the TME to shape a tumour-supportive environment in many types of cancer. Head and neck squamous cell carcinoma (HNSCC) encompass the malignant neoplasms arising from the mucosal lining of the oral cavity, pharynx and larynx. The TME of HNSCC contributes to tumour progression and this stromal compartment may be an interesting target for treatment. There is an emerging picture of the behaviour of CAFs in HNSCC; how they affect and are affected by the TME. We aim to summarise and discuss the current understanding of CAFs in head and neck cancer, exploring CAF activation and heterogeneity, and interaction with cancer cells and other cells within the TME.


Assuntos
Fibroblastos Associados a Câncer/metabolismo , Neoplasias de Cabeça e Pescoço/patologia , Microambiente Tumoral , Actinas/metabolismo , Animais , Biomarcadores , Fibroblastos Associados a Câncer/efeitos dos fármacos , Fibroblastos Associados a Câncer/patologia , Citocinas/metabolismo , Gerenciamento Clínico , Suscetibilidade a Doenças , Resistencia a Medicamentos Antineoplásicos , Metabolismo Energético , Transição Epitelial-Mesenquimal/genética , Transição Epitelial-Mesenquimal/imunologia , Exossomos/metabolismo , Fibroblastos/metabolismo , Neoplasias de Cabeça e Pescoço/etiologia , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias de Cabeça e Pescoço/terapia , Humanos , MicroRNAs/genética , Células-Tronco Neoplásicas/metabolismo , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/virologia , Microambiente Tumoral/imunologia
10.
Cell Death Discov ; 6: 77, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32864165

RESUMO

The hypoxic tumour is a chaotic landscape of struggle and adaption. Against the adversity of oxygen starvation, hypoxic cancer cells initiate a reprogramming of transcriptional activities, allowing for survival, metastasis and treatment failure. This makes hypoxia a crucial feature of aggressive tumours. Its importance, to cancer and other diseases, was recognised by the award of the 2019 Nobel Prize in Physiology or Medicine for research contributing to our understanding of the cellular response to oxygen deprivation. For cancers with limited treatment options, for example those that rely heavily on radiotherapy, the results of hypoxic adaption are particularly restrictive to treatment success. A fundamental aspect of this hypoxic reprogramming with direct relevance to radioresistance, is the alteration to the DNA damage response, a complex set of intermingling processes that guide the cell (for good or for bad) towards DNA repair or cell death. These alterations, compounded by the fact that oxygen is required to induce damage to DNA during radiotherapy, means that hypoxia represents a persistent obstacle in the treatment of many solid tumours. Considerable research has been done to reverse, correct or diminish hypoxia's power over successful treatment. Though many clinical trials have been performed or are ongoing, particularly in the context of imaging studies and biomarker discovery, this research has yet to inform clinical practice. Indeed, the only hypoxia intervention incorporated into standard of care is the use of the hypoxia-activated prodrug Nimorazole, for head and neck cancer patients in Denmark. Decades of research have allowed us to build a picture of the shift in the DNA repair capabilities of hypoxic cancer cells. A literature consensus tells us that key signal transducers of this response are upregulated, where repair proteins are downregulated. However, a complete understanding of how these alterations lead to radioresistance is yet to come.

12.
Mater Sci Eng C Mater Biol Appl ; 110: 110642, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32204075

RESUMO

In this work, a new tridentate ligand, its some novel zinc halide/pseudohalide complexes and their antimicrobial and cytotoxic effects of them are described. Characterization data of these compounds have been achieved via several physical and micro analytical techniques. As typical one, X-ray crystal structure analysis of zinc azide complex was run showing zinc center is penta-coordinated by three nitrogen atoms from Schiff base ligand and two terminal azide nitrogen atoms as a distorted square pyramidal geometry. Hirshfeld surfaces analysis clears the important role of interactions related to azide groups (NH⋯N and CH⋯N hydrogen bonds) in the stabilization of its supramolecular structure. According to data obtained from thermal analysis (TG/DTG/DTA), all complexes are decomposed at four or more thermal stages below 1000 °C. Moreover antimicrobial activities of the compounds were screened against some gram positive and gram negative bacteria. Furthermore anticancer activities of the complexes were studied against MDA-MB468 and k562 as two cancer cell lines. In final, three zinc complexes were also synthesized in nano scale by sonochemical method and one of them was utilized as the precursor for preparation of nanostructure ZnO confirmed by XRD pattern and SEM image.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Nanoestruturas/química , Temperatura , Zinco/química , Antifúngicos/farmacologia , Bactérias/efeitos dos fármacos , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Linhagem Celular Tumoral , Cristalografia por Raios X , Fragmentação do DNA/efeitos dos fármacos , Fungos/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Ligantes , Testes de Sensibilidade Microbiana , Conformação Molecular , Nanoestruturas/ultraestrutura , Espectroscopia de Prótons por Ressonância Magnética , Bases de Schiff/química , Espectrofotometria Ultravioleta , Vibração , Difração de Raios X
13.
Oncol Rep ; 43(3): 877-885, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32020221

RESUMO

Subjectivity in oral dysplasia grading has prompted evaluation of molecular­based tests to predict malignant transformation. Aneuploidy detected by DNA image­based cytometry (ICM) is currently the best predictor but fails to detect certain high risk lesions. A novel multiplex fluorescence in situ hybridization (FISH) panel was used to explore possible explanations by detecting aneuploidy at the single cell level. FISH was compared to reference standard DNA ICM in 19 oral lesions with epithelial dysplasia and used to characterize the cellular architecture. Copy number variation at 3q28, 7p11.2, 8q24.3, 11q13.3 and 20q13.12 and matched chromosome specific loci were assessed by dual­color FISH to assess numerical and spatial patterns of copy number increase and gene amplification. FISH revealed wide variation in copy number at different loci. Only low level copy number gain was present and often in only a small proportion of cells, although usually with all or all but one locus (9/12). Four cases showed gene amplification, one at two loci. Some probes revealed an internal presumed clonal structure within lesions not apparent in routine histological examination. Both methods produced similar diagnostic results with concordance in detection of aneuploidy by both methods in 17 out of 19 samples (89%). We have shown that oral dysplastic lesions may contain very few aneuploid cells at a cellular level, high copy number gain is rare and changes appear to arise from large chromosomal fragment duplications. Single stem lines are relatively homogeneous for loci with copy number gain but there is a subclonal structure revealed by gene amplification in some lesions.


Assuntos
Aneuploidia , Carcinoma in Situ/genética , Variações do Número de Cópias de DNA/genética , Neoplasias Bucais/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma in Situ/diagnóstico , Carcinoma in Situ/patologia , Aberrações Cromossômicas/classificação , DNA de Neoplasias/genética , Células Epiteliais/patologia , Feminino , Citometria de Fluxo , Amplificação de Genes/genética , Humanos , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/diagnóstico , Neoplasias Bucais/patologia
14.
Cancers (Basel) ; 11(12)2019 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-31817939

RESUMO

Cell death is a tightly regulated process which can be exploited in cancer treatment to drive the killing of the tumour. Several conventional cancer therapies including chemotherapeutic agents target pathways involved in cell death, yet they often fail due to the lack of selectivity they have for tumour cells over healthy cells. Over the past decade, research has demonstrated the existence of numerous proteins which have an intrinsic tumour-specific toxicity, several of which originate from viruses. These tumour-selective viral proteins, although from distinct backgrounds, have several similar and interesting properties. Though the mechanism(s) of action of these proteins are not fully understood, it is possible that they can manipulate several cell death modes in cancer exemplifying the intricate interplay between these pathways. This review will discuss our current knowledge on the topic and outstanding questions, as well as deliberate the potential for viral proteins to progress into the clinic as successful cancer therapeutics.

15.
Cell Death Dis ; 10(8): 540, 2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-31308358

RESUMO

Head and neck squamous cell carcinomas (HNSCCs) are an aggressive, genetically complex and difficult to treat group of cancers. In lieu of truly effective targeted therapies, surgery and radiotherapy represent the primary treatment options for most patients. But these treatments are associated with significant morbidity and a reduction in quality of life. Resistance to both radiotherapy and the only available targeted therapy, and subsequent relapse are common. Research has therefore focussed on identifying biomarkers to stratify patients into clinically meaningful groups and to develop more effective targeted therapies. However, as we are now discovering, the poor response to therapy and aggressive nature of HNSCCs is not only affected by the complex alterations in intracellular signalling pathways but is also heavily influenced by the behaviour of the extracellular microenvironment. The HNSCC tumour landscape is an environment permissive of these tumours' aggressive nature, fostered by the actions of the immune system, the response to tumour hypoxia and the influence of the microbiome. Solving these challenges now rests on expanding our knowledge of these areas, in parallel with a greater understanding of the molecular biology of HNSCC subtypes. This update aims to build on our earlier 2014 review by bringing up to date our understanding of the molecular biology of HNSCCs and provide insights into areas of ongoing research and perspectives for the future.


Assuntos
Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/terapia , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia , Biomarcadores Tumorais , Neoplasias de Cabeça e Pescoço/complicações , Neoplasias de Cabeça e Pescoço/metabolismo , Humanos , Imunoterapia Adotiva , Terapia de Alvo Molecular , Papillomaviridae , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/virologia , Transdução de Sinais/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/complicações , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Transcriptoma , Microambiente Tumoral/imunologia
16.
Mol Oncol ; 12(12): 2023-2041, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29959873

RESUMO

Head and neck squamous cell carcinomas (HNSCC) are associated with poor morbidity and mortality. Current treatment strategies are highly toxic and do not benefit over 50% of patients. There is therefore a crucial need for predictive and/or prognostic biomarkers to allow treatment stratification for individual patients. One class of biomarkers that has recently gained importance are microRNA (miRNA). MiRNA are small, noncoding molecules which regulate gene expression post-transcriptionally. We performed miRNA expression profiling of a cohort of head and neck tumours with known clinical outcomes. The results showed miR-9 to be significantly downregulated in patients with poor treatment outcome, indicating its role as a potential biomarker in HNSCC. Overexpression of miR-9 in HNSCC cell lines significantly decreased cellular proliferation and inhibited colony formation in soft agar. Conversely, miR-9 knockdown significantly increased both these features. Importantly, endogenous CXCR4 expression levels, a known target of miR-9, inversely correlated with miR-9 expression in a panel of HNSCC cell lines tested. Induced overexpression of CXCR4 in low expressing cells increased proliferation, colony formation and cell cycle progression. Moreover, CXCR4-specific ligand, CXCL12, enhanced cellular proliferation, migration, colony formation and invasion in CXCR4-overexpressing and similarly in miR-9 knockdown cells. CXCR4-specific inhibitor plerixafor abrogated the oncogenic phenotype of CXCR4 overexpression as well as miR-9 knockdown. Our data demonstrate a clear role for miR-9 as a tumour suppressor microRNA in HNSCC, and its role seems to be mediated through CXCR4 suppression. MiR-9 knockdown, similar to CXCR4 overexpression, significantly promoted aggressive HNSCC tumour cell characteristics. Our results suggest CXCR4-specific inhibitor plerixafor as a potential therapeutic agent, and miR-9 as a possible predictive biomarker of treatment response in HNSCC.


Assuntos
Antineoplásicos/farmacologia , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/genética , Compostos Heterocíclicos/farmacologia , MicroRNAs/genética , Receptores CXCR4/genética , Benzilaminas , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ciclamos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias de Cabeça e Pescoço/diagnóstico , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Invasividade Neoplásica/diagnóstico , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Invasividade Neoplásica/prevenção & controle , Prognóstico , Receptores CXCR4/antagonistas & inibidores , Resultado do Tratamento
17.
Trends Microbiol ; 25(11): 942-952, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28522156

RESUMO

Members of the epidermal growth factor receptor family (ErbB family) possess a wide distribution and diverse functions ranging from cellular growth to migration and apoptosis. Though highly implicated in a variety of cancers, their involvement in infectious disease is less recognised. A growing body of evidence now highlights the importance of the ErbB family in a variety of infections. Their role as growth factor receptors, along with other characteristics, such as surface expression and continuous intracellular trafficking, make this receptor family ideally placed for exploitation by pathogens. Herein, we review our current understanding of the role of the ErbB family in the context of infectious disease, exploring the mechanisms that govern pathogen exploitation of this system.


Assuntos
Doenças Transmissíveis/metabolismo , Família de Proteínas EGF/metabolismo , Receptores ErbB/metabolismo , Imunidade Adaptativa , Animais , Carcinogênese/metabolismo , Doenças Transmissíveis/genética , Doenças Transmissíveis/imunologia , Família de Proteínas EGF/genética , Receptores ErbB/genética , Receptores ErbB/imunologia , Interações Hospedeiro-Patógeno/imunologia , Humanos , Camundongos , Neoplasias/genética , Neoplasias/imunologia , Neoplasias/metabolismo
18.
Br J Cancer ; 116(8): 1057-1064, 2017 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-28324887

RESUMO

BACKGROUND: Hypoxia imaging is a promising tool for targeted therapy but the links between imaging features and underlying molecular characteristics of the tumour have not been investigated. The aim of this study was to compare hypoxia biomarkers and gene expression in oropharyngeal squamous cell carcinoma (OPSCC) diagnostic biopsies with hypoxia imaged with 64Cu-ATSM PET/CT. METHODS: 64Cu-ATSM imaging, molecular and clinical data were obtained for 15 patients. Primary tumour SUVmax, tumour to muscle ratio (TMR) and hypoxic volume were tested for association with reported hypoxia gene signatures in diagnostic biopsies. A putative gene signature for hypoxia in OPSCCs (hypoxic volume-associated gene signature (HVS)) was derived. RESULTS: Hypoxic volume was significantly associated with a reported hypoxia gene signature (rho=0.57, P=0.045), but SUVmax and TMR were not. Immunohistochemical staining with the hypoxia marker carbonic anhydrase 9 (CA9) was associated with a gene expression hypoxia response (rho=0.63, P=0.01). Sixteen genes were positively and five genes negatively associated with hypoxic volume (adjusted P<0.1; eight genes had adjusted P<0.05; HVS). This signature was associated with inferior 3-year progression-free survival (HR=1.5 (1.0-2.2), P=0.047) in an independent patient cohort. CONCLUSIONS: 64Cu-ATSM-defined hypoxic volume was associated with underlying hypoxia gene expression response. A 21-gene signature derived from hypoxic volume from patients with OPSCCs in our study may be linked to progression-free survival.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/patologia , Hipóxia/patologia , Neoplasias Orofaríngeas/patologia , Transcriptoma , Adulto , Idoso , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/genética , Radioisótopos de Cobre/metabolismo , Feminino , Humanos , Hipóxia/diagnóstico por imagem , Hipóxia/genética , Processamento de Imagem Assistida por Computador/métodos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Orofaríngeas/diagnóstico por imagem , Neoplasias Orofaríngeas/genética , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Prognóstico , Compostos Radiofarmacêuticos/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Tiossemicarbazonas/metabolismo
20.
Br J Cancer ; 116(1): 28-35, 2017 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-27884018

RESUMO

BACKGROUND: Patients with head and neck squamous cell carcinoma (HNSCC) undergoing radical chemo-radiation (CRT) frequently receive transfusion with packed red cells (PRCT) during radiotherapy on the basis that PRCT increases tumour oxygenation and overcomes hypoxia-induced radio-resistance. This is likely to be a significant oversimplification given the fact that tumour hypoxia is the result of several intrinsic and extrinsic factors, including many that are not directly related to serum haemoglobin (Hb). Therefore, we have studied the effect of PRCT on tumour oxygenation in a prospective cohort of patients who developed low Hb during radical CRT for HNSCC. METHODS: This was a prospective study of 20 patients with HNSCC receiving radical CRT undergoing PRCT for Hb<11.5 g dl-1. Patients underwent pretransfusion and posttransfusion intrinsic susceptibility-weighted (SWI) MRI and dynamic contrast-enhanced (DCE) MRI. Blood samples were obtained at the time of MRI scanning and two further time points for measuring Hb and a panel of serum cytokine markers of tumour hypoxia. 3D T2* and Ktrans maps were calculated from the MRI data for primary tumours and cervical lymph node metastases. RESULTS: PRCT produced no change (11 patients) or reduced (1 patient) T2* (tumour oxygenation) in 12 of the 16 (75%) evaluable primary tumours. Three of the four patients with improved tumour oxygenation progressed or had partial response following treatment completion. There were variable changes in Ktrans (tumour perfusion or vessel permeability) following PRCT that were of small magnitude for most tumours. Pre- and Post-PRCT levels of measured cytokines were not significantly different. CONCLUSIONS: This study suggests that PRCT during radical CRT for HNSCC does not improve tumour oxygenation. Therefore, oncologists should consider changing practice according to NICE and American Association of Blood Banks guidelines on PRCT for anaemia.


Assuntos
Transfusão de Sangue , Carcinoma de Células Escamosas/terapia , Quimiorradioterapia , Neoplasias de Cabeça e Pescoço/terapia , Hipóxia Tumoral , Idoso , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/patologia , Feminino , Neoplasias de Cabeça e Pescoço/diagnóstico , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Estudos Longitudinais , Metástase Linfática , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Carcinoma de Células Escamosas de Cabeça e Pescoço , Hipóxia Tumoral/efeitos dos fármacos
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